CN115611776A - Industrial method for purifying IPDI (isophorone diisocyanate) crude product - Google Patents
Industrial method for purifying IPDI (isophorone diisocyanate) crude product Download PDFInfo
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- CN115611776A CN115611776A CN202211197190.1A CN202211197190A CN115611776A CN 115611776 A CN115611776 A CN 115611776A CN 202211197190 A CN202211197190 A CN 202211197190A CN 115611776 A CN115611776 A CN 115611776A
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- NIMLQBUJDJZYEJ-UHFFFAOYSA-N isophorone diisocyanate Chemical compound CC1(C)CC(N=C=O)CC(C)(CN=C=O)C1 NIMLQBUJDJZYEJ-UHFFFAOYSA-N 0.000 title claims abstract description 91
- 239000005058 Isophorone diisocyanate Substances 0.000 title claims abstract description 90
- 239000012043 crude product Substances 0.000 title claims abstract description 37
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 36
- LRHPLDYGYMQRHN-UHFFFAOYSA-N N-Butanol Chemical compound CCCCO LRHPLDYGYMQRHN-UHFFFAOYSA-N 0.000 claims abstract description 48
- 239000000047 product Substances 0.000 claims abstract description 41
- 239000000463 material Substances 0.000 claims abstract description 34
- HJOVHMDZYOCNQW-UHFFFAOYSA-N isophorone Chemical compound CC1=CC(=O)CC(C)(C)C1 HJOVHMDZYOCNQW-UHFFFAOYSA-N 0.000 claims abstract description 13
- 238000010467 ester pyrolysis Methods 0.000 claims abstract description 5
- 239000002253 acid Substances 0.000 claims abstract description 4
- 125000004108 n-butyl group Chemical group [H]C([H])([H])C([H])([H])C([H])([H])C([H])([H])* 0.000 claims abstract description 3
- 238000005979 thermal decomposition reaction Methods 0.000 claims description 37
- 238000000034 method Methods 0.000 claims description 36
- 239000002904 solvent Substances 0.000 claims description 12
- 239000003054 catalyst Substances 0.000 claims description 10
- -1 n-butyl isophorone dicarbamate Chemical compound 0.000 claims description 9
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 claims description 8
- 239000004202 carbamide Substances 0.000 claims description 8
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 claims description 4
- NMJJFJNHVMGPGM-UHFFFAOYSA-N n-butylmethanoate Natural products CCCCOC=O NMJJFJNHVMGPGM-UHFFFAOYSA-N 0.000 claims description 4
- 238000002360 preparation method Methods 0.000 claims description 4
- 238000000746 purification Methods 0.000 claims description 4
- JIAARYAFYJHUJI-UHFFFAOYSA-L zinc dichloride Chemical compound [Cl-].[Cl-].[Zn+2] JIAARYAFYJHUJI-UHFFFAOYSA-L 0.000 claims description 4
- 239000013132 MOF-5 Substances 0.000 claims description 2
- XBXFGOSIPGWNLZ-UHFFFAOYSA-N O=C1C=C(CC(C)(C)C1)C.N=C=O Chemical compound O=C1C=C(CC(C)(C)C1)C.N=C=O XBXFGOSIPGWNLZ-UHFFFAOYSA-N 0.000 claims description 2
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 claims description 2
- ZOIORXHNWRGPMV-UHFFFAOYSA-N acetic acid;zinc Chemical compound [Zn].CC(O)=O.CC(O)=O ZOIORXHNWRGPMV-UHFFFAOYSA-N 0.000 claims description 2
- WMWLMWRWZQELOS-UHFFFAOYSA-N bismuth(III) oxide Inorganic materials O=[Bi]O[Bi]=O WMWLMWRWZQELOS-UHFFFAOYSA-N 0.000 claims description 2
- 229940046374 chromium picolinate Drugs 0.000 claims description 2
- GJYSUGXFENSLOO-UHFFFAOYSA-N chromium;pyridine-2-carboxylic acid Chemical compound [Cr].OC(=O)C1=CC=CC=N1.OC(=O)C1=CC=CC=N1.OC(=O)C1=CC=CC=N1 GJYSUGXFENSLOO-UHFFFAOYSA-N 0.000 claims description 2
- 239000002608 ionic liquid Substances 0.000 claims description 2
- 238000000197 pyrolysis Methods 0.000 claims description 2
- ROPPTGKKZZDFJN-UHFFFAOYSA-N trinonyl benzene-1,2,4-tricarboxylate Chemical compound CCCCCCCCCOC(=O)C1=CC=C(C(=O)OCCCCCCCCC)C(C(=O)OCCCCCCCCC)=C1 ROPPTGKKZZDFJN-UHFFFAOYSA-N 0.000 claims description 2
- JNXDCMUUZNIWPQ-UHFFFAOYSA-N trioctyl benzene-1,2,4-tricarboxylate Chemical compound CCCCCCCCOC(=O)C1=CC=C(C(=O)OCCCCCCCC)C(C(=O)OCCCCCCCC)=C1 JNXDCMUUZNIWPQ-UHFFFAOYSA-N 0.000 claims description 2
- 239000011701 zinc Substances 0.000 claims description 2
- 229910052725 zinc Inorganic materials 0.000 claims description 2
- 239000004246 zinc acetate Substances 0.000 claims description 2
- 239000011592 zinc chloride Substances 0.000 claims description 2
- 235000005074 zinc chloride Nutrition 0.000 claims description 2
- 239000011787 zinc oxide Substances 0.000 claims description 2
- 229940032991 zinc picolinate Drugs 0.000 claims description 2
- ADJMNWKZSCQHPS-UHFFFAOYSA-L zinc;6-methylheptanoate Chemical compound [Zn+2].CC(C)CCCCC([O-])=O.CC(C)CCCCC([O-])=O ADJMNWKZSCQHPS-UHFFFAOYSA-L 0.000 claims description 2
- XKMZOFXGLBYJLS-UHFFFAOYSA-L zinc;prop-2-enoate Chemical compound [Zn+2].[O-]C(=O)C=C.[O-]C(=O)C=C XKMZOFXGLBYJLS-UHFFFAOYSA-L 0.000 claims description 2
- NHVUUBRKFZWXRN-UHFFFAOYSA-L zinc;pyridine-2-carboxylate Chemical compound C=1C=CC=NC=1C(=O)O[Zn]OC(=O)C1=CC=CC=N1 NHVUUBRKFZWXRN-UHFFFAOYSA-L 0.000 claims description 2
- SKKTUOZKZKCGTB-UHFFFAOYSA-N butyl carbamate Chemical compound CCCCOC(N)=O SKKTUOZKZKCGTB-UHFFFAOYSA-N 0.000 claims 1
- 238000009833 condensation Methods 0.000 claims 1
- 230000005494 condensation Effects 0.000 claims 1
- 238000004821 distillation Methods 0.000 claims 1
- 238000002207 thermal evaporation Methods 0.000 claims 1
- 230000015572 biosynthetic process Effects 0.000 abstract description 4
- 239000007788 liquid Substances 0.000 abstract description 3
- 238000003786 synthesis reaction Methods 0.000 abstract description 3
- 238000006243 chemical reaction Methods 0.000 description 23
- 239000012071 phase Substances 0.000 description 17
- YGYAWVDWMABLBF-UHFFFAOYSA-N Phosgene Chemical compound ClC(Cl)=O YGYAWVDWMABLBF-UHFFFAOYSA-N 0.000 description 13
- 125000005442 diisocyanate group Chemical group 0.000 description 12
- 239000012948 isocyanate Substances 0.000 description 10
- 150000002513 isocyanates Chemical class 0.000 description 9
- 235000013877 carbamide Nutrition 0.000 description 8
- 239000007789 gas Substances 0.000 description 8
- 230000008569 process Effects 0.000 description 7
- 150000001412 amines Chemical class 0.000 description 6
- 238000004227 thermal cracking Methods 0.000 description 6
- 239000013638 trimer Substances 0.000 description 6
- KXDHJXZQYSOELW-UHFFFAOYSA-M Carbamate Chemical compound NC([O-])=O KXDHJXZQYSOELW-UHFFFAOYSA-M 0.000 description 5
- 150000004985 diamines Chemical class 0.000 description 5
- 239000004814 polyurethane Substances 0.000 description 5
- 229920002635 polyurethane Polymers 0.000 description 5
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 4
- 239000006227 byproduct Substances 0.000 description 4
- 238000011161 development Methods 0.000 description 4
- 239000007791 liquid phase Substances 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 3
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 3
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- ZMANZCXQSJIPKH-UHFFFAOYSA-N Triethylamine Chemical compound CCN(CC)CC ZMANZCXQSJIPKH-UHFFFAOYSA-N 0.000 description 3
- 238000003776 cleavage reaction Methods 0.000 description 3
- 239000000539 dimer Substances 0.000 description 3
- IEJIGPNLZYLLBP-UHFFFAOYSA-N dimethyl carbonate Chemical compound COC(=O)OC IEJIGPNLZYLLBP-UHFFFAOYSA-N 0.000 description 3
- IXCSERBJSXMMFS-UHFFFAOYSA-N hydrogen chloride Substances Cl.Cl IXCSERBJSXMMFS-UHFFFAOYSA-N 0.000 description 3
- 229910000041 hydrogen chloride Inorganic materials 0.000 description 3
- 239000002994 raw material Substances 0.000 description 3
- 230000007017 scission Effects 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 2
- 239000004642 Polyimide Substances 0.000 description 2
- 150000008065 acid anhydrides Chemical class 0.000 description 2
- 150000001408 amides Chemical class 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- 238000005260 corrosion Methods 0.000 description 2
- 230000007797 corrosion Effects 0.000 description 2
- 238000000354 decomposition reaction Methods 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 150000002148 esters Chemical class 0.000 description 2
- BDAGIHXWWSANSR-UHFFFAOYSA-N methanoic acid Natural products OC=O BDAGIHXWWSANSR-UHFFFAOYSA-N 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- 239000003973 paint Substances 0.000 description 2
- 229920001721 polyimide Polymers 0.000 description 2
- 238000006116 polymerization reaction Methods 0.000 description 2
- 150000003512 tertiary amines Chemical class 0.000 description 2
- 239000010409 thin film Substances 0.000 description 2
- RNLHGQLZWXBQNY-UHFFFAOYSA-N 3-(aminomethyl)-3,5,5-trimethylcyclohexan-1-amine Chemical compound CC1(C)CC(N)CC(C)(CN)C1 RNLHGQLZWXBQNY-UHFFFAOYSA-N 0.000 description 1
- OSWFIVFLDKOXQC-UHFFFAOYSA-N 4-(3-methoxyphenyl)aniline Chemical compound COC1=CC=CC(C=2C=CC(N)=CC=2)=C1 OSWFIVFLDKOXQC-UHFFFAOYSA-N 0.000 description 1
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 1
- 239000004970 Chain extender Substances 0.000 description 1
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 1
- 241001449342 Chlorocrambe hastata Species 0.000 description 1
- JOYRKODLDBILNP-UHFFFAOYSA-N Ethyl urethane Chemical compound CCOC(N)=O JOYRKODLDBILNP-UHFFFAOYSA-N 0.000 description 1
- ZHNUHDYFZUAESO-UHFFFAOYSA-N Formamide Chemical group NC=O ZHNUHDYFZUAESO-UHFFFAOYSA-N 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 150000007945 N-acyl ureas Chemical class 0.000 description 1
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N Phenol Chemical compound OC1=CC=CC=C1 ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 description 1
- 229920002396 Polyurea Polymers 0.000 description 1
- UKLDJPRMSDWDSL-UHFFFAOYSA-L [dibutyl(dodecanoyloxy)stannyl] dodecanoate Chemical compound CCCCCCCCCCCC(=O)O[Sn](CCCC)(CCCC)OC(=O)CCCCCCCCCCC UKLDJPRMSDWDSL-UHFFFAOYSA-L 0.000 description 1
- 230000002159 abnormal effect Effects 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 125000001931 aliphatic group Chemical group 0.000 description 1
- 150000001338 aliphatic hydrocarbons Chemical class 0.000 description 1
- 150000004945 aromatic hydrocarbons Chemical class 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- OHJMTUPIZMNBFR-UHFFFAOYSA-N biuret Chemical compound NC(=O)NC(N)=O OHJMTUPIZMNBFR-UHFFFAOYSA-N 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 150000004657 carbamic acid derivatives Chemical class 0.000 description 1
- 150000001715 carbamic acids Chemical class 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 229910002092 carbon dioxide Inorganic materials 0.000 description 1
- 230000006315 carbonylation Effects 0.000 description 1
- 238000005810 carbonylation reaction Methods 0.000 description 1
- 239000000460 chlorine Substances 0.000 description 1
- 229910052801 chlorine Inorganic materials 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 238000004132 cross linking Methods 0.000 description 1
- 125000004122 cyclic group Chemical group 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000012975 dibutyltin dilaurate Substances 0.000 description 1
- 238000007865 diluting Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 229920001971 elastomer Polymers 0.000 description 1
- 239000000806 elastomer Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 239000010408 film Substances 0.000 description 1
- 235000019253 formic acid Nutrition 0.000 description 1
- 150000004675 formic acid derivatives Chemical class 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 230000003301 hydrolyzing effect Effects 0.000 description 1
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 1
- 150000003949 imides Chemical group 0.000 description 1
- 230000008676 import Effects 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 239000012442 inert solvent Substances 0.000 description 1
- 230000002427 irreversible effect Effects 0.000 description 1
- 150000002576 ketones Chemical class 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- ZZHGIUCYKGFIPV-UHFFFAOYSA-M n-butylcarbamate Chemical compound CCCCNC([O-])=O ZZHGIUCYKGFIPV-UHFFFAOYSA-M 0.000 description 1
- 230000003472 neutralizing effect Effects 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 238000012856 packing Methods 0.000 description 1
- 150000003141 primary amines Chemical class 0.000 description 1
- 238000011112 process operation Methods 0.000 description 1
- 239000003380 propellant Substances 0.000 description 1
- 238000005086 pumping Methods 0.000 description 1
- 230000009257 reactivity Effects 0.000 description 1
- 230000008707 rearrangement Effects 0.000 description 1
- 239000003507 refrigerant Substances 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
- 230000002441 reversible effect Effects 0.000 description 1
- 150000003335 secondary amines Chemical class 0.000 description 1
- 125000000467 secondary amino group Chemical group [H]N([*:1])[*:2] 0.000 description 1
- 238000007086 side reaction Methods 0.000 description 1
- 239000000779 smoke Substances 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 150000005846 sugar alcohols Polymers 0.000 description 1
- 238000001308 synthesis method Methods 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
- 239000011269 tar Substances 0.000 description 1
- 239000002341 toxic gas Substances 0.000 description 1
- AVWRKZWQTYIKIY-UHFFFAOYSA-N urea-1-carboxylic acid Chemical compound NC(=O)NC(O)=O AVWRKZWQTYIKIY-UHFFFAOYSA-N 0.000 description 1
- 150000003672 ureas Chemical class 0.000 description 1
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Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C263/00—Preparation of derivatives of isocyanic acid
- C07C263/18—Separation; Purification; Stabilisation; Use of additives
- C07C263/20—Separation; Purification
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C2601/00—Systems containing only non-condensed rings
- C07C2601/12—Systems containing only non-condensed rings with a six-membered ring
- C07C2601/14—The ring being saturated
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention relates to the technical field of industrial synthesis of IPDI, in particular to an industrial method for purifying an IPDI crude product, which comprises the following steps: s1, feeding the IPDI crude product into a first rectifying tower for rectifying operation, extracting n-butyl alcohol from the tower top, extracting IPDI rich solution from the side line in the middle of the tower, and removing isophorone diamino formic acid n-butyl ester pyrolysis unit from the tower bottom material; s2, allowing IPDI rich liquid to enter a second rectifying tower for rectifying operation, extracting n-butyl alcohol and IPDI from the tower top, extracting an IPDI product from the middle side line of the tower, and removing materials in the tower bottom to an isophorone diamino acid n-butyl ester pyrolysis unit. After the IPDI crude product is treated by the industrial method for purifying the IPDI crude product, the purity of the obtained IPDI product is more than 99.7 percent.
Description
Technical Field
The invention relates to the technical field of industrial synthesis of IPDI, in particular to an industrial method for purifying an IPDI crude product.
Background
Isophorone diisocyanic acidThe chemical name of the acid ester is 3-isocyanatomethylene-3, 5-trimethylcyclohexyl isocyanate, and the English name is IPDI. Molecular formula C 12 H 18 N 2 O 2 Structural formula (II)
The molecular weight is 222.29, the product is colorless or light yellow liquid, has camphoraceous odor, and is completely miscible with organic solvents such as ester, ketone, ether, aromatic hydrocarbon and aliphatic hydrocarbon.
Diisocyanates contain two-N = C = O groups, which are highly reactive due to electronic imbalance and unsaturation. The common chemical reactions are as follows:
reaction with water:
the reaction of diisocyanates with water to form unstable carbamic acids and rapidly decompose to the diisocyanate's native diamines with evolution of carbon dioxide occurs at ambient conditions.
If the diisocyanate is in excess, the resulting diamine will continue to react with the diisocyanate to form urea and further react to form biuret.
OCNRCH 2 NCO+NH 2 RCH 2 NH 2 →OCNRCH 2 NHCONHRCH 2 NH 2
OCNRCH 2 NCO+OCNRCH 2 NHCONHRCH 2 NH 2
→OCNRCH 2 NHCONHRCH 2 NHCNHRCH 2 NCO
Reaction with hydroxyl groups:
in general, an-OH-containing substance such as an alcohol or phenol reacts with a diisocyanate to form a urethane, and reacts with a dihydric or higher polyhydric alcohol to form a polyurethane.
OCNRNCO+2R'OH→R'OCONHRCH 2 NHCOOR'
This is also the principle of production of polyurethanes, which is the main use of diisocyanates.
Reaction with amine:
the reaction with primary and secondary amines produces substituted ureas (polyurea elastomers), while the tertiary amines do not contain active hydrogen and the diisocyanates do not react with the tertiary amines.
OCNRCH 2 NCO+NH 2 R'→CONRCH 2 NHCONHR'
OCNRCH 2 NCO+2NH 2 R'→R'NHOCNHRCH 2 NHCONHR'
OCNRCH 2 NCO+NHR'R"→CONRCH 2 NHCONR'R"
It is based on the above reaction that diamines are often used as cross-linking and chain extenders and triethylamine as neutralizing agent in the production of polyurethanes. On the other hand, in the cleavage units of HDI and IPDI, since the cleavage raw material dicarbamate contains two secondary amino groups (-NH), and the dicarbamate may contain amine and diamine and other amine substances in the by-product under high temperature conditions, IPDI as a product is reacted with the raw material and further polymerized. Thus, to the extent that the cleavage of the ADU to produce polyurethane is considered a reversible, bi-directional reaction, a pair of spearheads is utilized.
Reaction with Carbamate:
the reactivity is low and it takes more than 120 ℃ to react and generate allophanate product.
Reaction with acid anhydride:
the isocyanate reacts with the acid anhydride to form an imide ring having high heat resistance, and further reaction can form Polyimide (PI) having higher thermal stability.
Reaction with amide:
the isocyanate reacts with the amide to form an acylurea.
RNCO+H 2 NCOR'→RNHCONHCOR'
Self-polymerization reaction:
IPDI undergoes self-polymerization under the action of heat and a catalyst (such as dibutyltin dilaurate), and dimers, trimers and even multimers are formed at higher temperatures.
Two IPDIs self-polymerize into IPDI dimer:
the dimer is an unstable compound, and is reduced to IPDI by heating decomposition, or continuously polymerized to trimer.
Unlike dimers, the reaction of trimers is irreversible and the thermal decomposition products of trimers are not IPDI. The trimer has the advantages of stable structure, difficult decomposition at high temperature, good thermal stability, good wear resistance, good corrosion resistance and the like, can quickly release a solvent, has higher reaction activity because the trimer still contains a group of-N = C = O, and is often used as a polyurethane curing agent to be widely applied to industries of furniture, automobiles, aviation and the like.
The production method of isophorone diisocyanate mainly comprises a phosgene method and a thermal cracking method of carbamate. The phosgene method is still the main production method of diisocyanate at present, only 1 million tons per year of production devices are respectively built in the non-phosgene method of only Degussa and Basff, and domestic production is still blank.
The gas phase phosgenation process is a process for preparing isocyanate by diluting gaseous amines with inert gas or steam of inert solvent, feeding them into a mixing reactor together with phosgene, and reacting at 200-600 ℃. The gas phase method is a latest phosgenation method, and compared with the traditional liquid phase phosgenation method, the gas phase method has the advantages of less phosgene usage, extremely fast reaction rate, high yield (more than 98 percent) and low risk. At present, bayer uses this method to produce HDI and IPDI, and the yield accounts for more than 70% of HDI production. The only IPDI production enterprise in China also adopts the process.
The amine phosgene method mainly has the following problems: (1) phosgene is a highly toxic gas, and a series of engineering technical problems of safety, environmental protection and the like in the production process are difficult to solve; (2) a large amount of byproduct hydrogen chloride exists in the production of the phosgene method, and if the absorption treatment is incomplete, the hydrogen chloride also leaks to cause environmental pollution; (3) the byproduct hydrogen chloride has serious corrosion to equipment in the production process, has higher requirement on equipment materials and has larger corresponding equipment investment; (4) isocyanate products produced by the phosgene method contain hydrolytic chlorine, which affects the service performance of the products.
Since the phosgene method has the above disadvantages, developed countries have been devoted to develop an economical and simple synthesis method, and thus various non-phosgene methods for synthesizing isocyanates have appeared, such as carbonylation method, thermal decomposition of chlorinated formamide, crutius rearrangement method, reaction of amine and chlorinated formate, thermal decomposition of carbamate, etc., but most of them are still in laboratory stage, and only the thermal decomposition of carbamate realizes the production in an apparatus abroad.
The starting materials for preparing carbamates include, mainly, urea method and dialkyl carbonate method.
The technique of preparing carbamate by dimethyl carbonate and preparing ADI by thermal cracking attracts attention, the method has the characteristics of easy reaction, simple control and higher yield, and the generated methanol can be recycled to further prepare dimethyl carbonate. However, the manufacturing cost of dimethyl carbonate is high, which limits the industrial application of the method.
The urea route has been studied most, the process is mature and has been used industrially (abroad). The process for preparing isocyanate by the urea method comprises two steps, namely reacting urea, diamine and alcohol to generate dicarbamate, and thermally cracking the dicarbamate to generate the isocyanate and the alcohol, wherein the total reaction yield can reach 90%.
The thermal cracking reaction may be carried out in the liquid phase or in the gas phase. The gas phase thermal cracking is a high-temperature process, generally the temperature is higher than 300 ℃, and the reaction can be carried out with or without a catalyst; the liquid phase thermal cracking process is generally carried out at temperatures below 300 deg.C, usually with the addition of a catalyst and a high boiling point solvent. Thermal decomposition is often accompanied by the formation of many side reactions, such as tars, resinous polymeric byproducts, which not only reduce yield, but also plug reactors and other equipment.
The development and production of diisocyanate in China are relatively late, but with the rapid development of society and economy in China, the diisocyanate has become a world-wide production and consumption country, wherein MDI and TDI account for more than 85% of the total amount of the diisocyanate. On the other hand, in the field of high-performance special isocyanate, the development of China is very slow, and the consumption demand is increased at a speed of more than 15% per year. The aliphatic isocyanate is mainly applied to the fields of automobile finish, rocket propellant, anticorrosive paint, photocureable paint, adhesive and the like. Due to the historical reason of the introduction of the technology, the high-grade coating used in the industries of automobiles, high-speed trains, airplanes, steamships, luxury coaches, wooden furniture, buildings and the like in China is completely occupied by foreign products, and one of the restricting factors is the key raw material aliphatic diisocyanate.
At present, HDI and IPDI in China have annual demand of about 9.5 ten thousand tons and are mainly occupied by a few international companies such as winning and creating companies, degussa companies and the like. HDI is built with 3 million tons/year, 1.5 million tons/year smoke station, and most products of Bayer are exported and the price is high; IPDI is only used for building 1.5 million tons per year of devices in the world by adopting a phosgene method, the operation is abnormal all the time, and only a small amount of products enter the market. The domestic product requirements basically depend on import, and due to well-known reasons, part of high-end military varieties are sold to the limit of China.
Based on the great significance of IPDI on national economy and industrial safety and the fact that the domestic production development lags behind, the applicant annually produces a project of producing aliphatic (cyclo) group isocyanate (IPDI) by using a non-phosgene method of 2000 tons and is listed as a national key research and development project. The invention provides an industrial method for purifying IPDI (isophorone diisocyanate) crude products, which breaks through the technical monopoly of industrialized urea method IPDI synthesis in developed countries.
Disclosure of Invention
The invention aims to provide an industrial method for purifying IPDI (isophorone diisocyanate) crude products.
The purpose of the invention is realized by the following technical scheme: an industrial method for purifying IPDI crude product comprises the following steps:
s1, feeding IPDI (isophorone diisocyanate) crude products into a first rectifying tower for rectifying operation, extracting n-butyl alcohol from the tower top, extracting IPDI (isophorone diamine formic acid) pregnant solution from the side line of the middle part of the tower, and removing materials at the tower bottom into an isophorone diamino n-butyl formate pyrolysis unit; among them, the thermal decomposition reaction of n-butyl isophorone dicarbamate is a thermal decomposition reaction of n-butyl isophorone dicarbamate, and the thermal decomposition reaction of n-butyl isophorone dicarbamate is a first thermal decomposition reaction and/or a second thermal decomposition reaction indicated below, and is preferably a second thermal decomposition reaction.
S2, allowing IPDI rich liquid to enter a second rectifying tower for rectifying operation, extracting n-butyl alcohol and IPDI from the tower top, extracting an IPDI product from the middle side line of the tower, and removing materials in the tower bottom to an isophorone diamino acid n-butyl ester pyrolysis unit.
Further, the operating pressure of the first rectifying tower is 10-30mbar, the temperature of a tower kettle is 190-210 ℃, the operating temperature of a tower top is 20-30 ℃, and the temperature of a lateral line is 150-170 ℃; preferably, the operating pressure of the first rectifying tower is 10-25mbar, the temperature of the tower bottom is 199-202 ℃, the operating temperature of the tower top is 24-26 ℃, and the temperature of the lateral line is 159.5-161.5 ℃.
And/or the operating pressure of the second rectifying tower is 10-30mbar, the temperature of a tower kettle is 190-200 ℃, the operating temperature of a tower top is 30-50 ℃, and the temperature of a lateral line is 155-160 ℃; preferably, the operating pressure of the second rectifying tower is 10-25mbar, the tower bottom temperature is 193-195 ℃, the tower top operating temperature is 39-41 ℃, and the side line temperature is 158-159 ℃.
Further, the IPDI crude product is characterized in that the content ranges of the components and the contents of the IPDI crude product are 18-30wt% of n-butyl alcohol, 20-45wt% of IPDI, 20-45wt% of isophorone isocyanate group single n-butyl carbamate (single side) and 7-15wt% of naphthenic oil.
Further, the IPDI crude product comprises a first crude product, and the preparation method of the first crude product comprises the following steps: and carrying out a first thermal decomposition reaction on isophorone diamino n-butyl formate, a solvent and a catalyst to obtain a gas phase material I, wherein the gas phase material I is the first crude product.
Further, the IPDI crude product also comprises a second crude product, and the preparation method of the second crude product comprises the following steps: and (3) carrying out a second thermal decomposition reaction on the tower bottom material obtained in the step (S1) and/or the step (S2) to obtain a gas-phase material III, wherein the gas-phase material III is the second crude product.
Further, the pressure of the first thermal decomposition reaction is controlled to be-0.08 to-0.098 MPa, and the temperature is controlled to be 200 to 280 ℃; preferred ranges are: the pressure is-0.092 to-0.098 MPa, and the temperature is 220 to 260 ℃;
and/or the pressure of the second thermal decomposition reaction is controlled to be-0.08 to-0.098 MPa, and the temperature is controlled to be 200 to 280 ℃; preferred ranges are: the pressure is-0.092 to-0.098 MPa, and the temperature is 220 to 260 ℃.
Further, the temperature of the second thermal decomposition reaction is 1 to 10 ℃, preferably 4 to 8 ℃ higher than the temperature of the first thermal decomposition reaction.
Further, the mole ratio of the isophorone diamino n-butyl formate, the solvent and the catalyst is as follows: 1:0-9:0.0025-0.015. Preferably, the mass ratio of the isophorone butyl dicarbamate to the solvent to the catalyst is as follows: 1:0.67-9:0.003-0.010.
Further, the n-butyl isophorone dicarbamate is an n-butyl isophorone dicarbamate product synthesized by a urea method;
the solvent is one of naphthenic oil, trioctyl trimellitate and trinonyl trimellitate;
the catalyst is one or more of zinc picolinate, chromium picolinate, MOF-5, zinc oxide, bismuth trioxide, ionic liquid zinc, zinc chloride, zinc acetate, zinc acrylate and zinc isooctanoate.
Furthermore, heavy component materials are obtained through the first thermal decomposition reaction and the second thermal decomposition reaction, and the heavy component materials need to be discharged through the first thermal decomposition reaction and the second thermal decomposition reaction.
Further, the discharged heavy component material is heated and evaporated to obtain a gas-phase product and residue, and the gas-phase product can be used as a solvent after being condensed.
Further, the reactor of the first thermal decomposition reaction and/or the second thermal decomposition reaction is a thin film evaporator. Preferably, the thin film evaporator is a wiped film evaporator.
The invention has the beneficial effects that: after the IPDI crude product is treated by the industrial method for purifying the IPDI crude product, the purity of the obtained IPDI product is more than 99.7 percent.
Drawings
FIG. 1 is a process flow diagram for the purification of crude IPDI;
FIG. 2 is a flow chart of the thermal cracking process of isophorone carbamic acid n-butyl ester industrially used in the present invention.
Detailed Description
The technical solutions of the present invention are described in further detail below, but the scope of the present invention is not limited to the following.
1. Reactor for rectification, reaction process and detection method
(1) Reaction equipment
Light component removal column (rectifying column): phi 1200 is multiplied by 24604, and the height of the filler is 3888/3888/3888/3240mm
Product column (rectification column): phi 900X 24348, packing height 3096/3096/4128/4128mm
A condenser: condenser phi 1200 is multiplied by 2000 at the top of the light component removing tower, and the heat exchange area is 80m 2 (ii) a Product tower top condenser phi 1000 x 2000 and heat exchange area 90m 2
A reboiler: reboiler at bottom of light component removing tower with phi 1100 x 2500 and heat exchange area of 94.5m 2 (ii) a Reboiler at tower bottom of product with phi 1400 multiplied by 3000 and heat exchange area of 190m 2
Circulating pump: circulating pump Q =10.8m at bottom of light component removing tower 3 H =40m Zone2 EEx dII BT4, product bottom circulating pump Q =18m 3 H＝40m Zone2 EEx dII BT4
An auxiliary system: the heat conducting oil system provides required heat source, the circulating water system and the chilled water system provide refrigerant, the nitrogen system provides nitrogen for the replacement of the start-stop system, and the vacuum system provides the required vacuum condition for the device
The control system comprises: the process operation control adopts a DCS system and is provided with a Safety Interlock System (SIS)
(2) Reaction scheme
And (3) feeding the gas-phase IPDI crude product (gas-phase material I and/or gas-phase material III) into the bottom of a light component removal tower (a first rectifying tower) from a thermal decomposition unit, extracting n-butyl alcohol from the top of the tower, extracting IPDI rich solution from the side line of the middle part of the tower, and circularly thermally decomposing the tower kettle material in the thermal decomposition unit (a second thermal decomposition reaction). Pumping the IPDI rich solution extracted from the side line of the light component removal tower into a product tower (a second rectifying tower), extracting a small amount of n-butyl alcohol plus IPDI from the tower top, extracting an IPDI product from the side line, and performing cyclic thermal decomposition (a second thermal decomposition reaction) on a tower kettle material (a liquid phase material II) by a thermal decomposition unit.
(3) Detection method
See table 1:
TABLE 1
2. Method for purifying IPDI (isophorone diisocyanate) crude product
Example 1
The crude product of the gas-phase IPDI comprises 19.54 percent of n-butanol, 28.64 percent of IPDI, 39.52 percent of single side and 12.3 percent of naphthenic oil (solvent).
The operating conditions of the lightness-removing column are controlled as follows: the tower top is 11mbar, the tower kettle is 24mbar, the tower kettle temperature is 199.7 ℃, the tower top operating temperature is 25 ℃, and the lateral line temperature is 160.8 ℃; the operating conditions of the product column were: 11mbar at the top of the tower, 24mbar at the bottom of the tower, 194 ℃ at the bottom of the tower, 40 ℃ at the top of the tower and 158.3 ℃ at the lateral line.
Taking n-butyl alcohol extracted from the top of the light component removal tower, IPDI rich solution extracted from the side line of the middle part of the tower and tower kettle materials; and taking n-butanol and IPDI extracted from the top of the product tower, IPDI products extracted from the middle part of the tower in a side line manner, and tower kettle materials. The components and contents were measured separately, and the results are shown in the following table 2:
TABLE 2
Example 2
The crude product of the gas-phase IPDI comprises 22.94% of n-butanol, 31.97% of IPDI, 34.63% of unilateral and 10.46% of naphthenic oil.
The operating conditions of the lightness-removing column are controlled as follows: the tower top is 11mbar, the tower kettle is 24mbar, the temperature of the tower kettle is 200.4 ℃, the operation temperature of the tower top is 25.5 ℃, and the lateral line temperature is 161 ℃; the operating conditions of the product column were: the top of the tower is 11mbar, the bottom of the tower is 24mbar, the temperature of the bottom of the tower is 194.5 ℃, the operation temperature of the top of the tower is 40.5 ℃, and the temperature of the lateral line is 158.5 ℃.
Taking n-butanol extracted from the top of the light component removal tower, IPDI rich solution extracted from the middle side of the tower and tower kettle materials; and taking n-butanol and IPDI extracted from the top of the product tower, IPDI products extracted from the middle part of the tower in a side line manner, and tower kettle materials. The components and contents were measured separately, and the results are shown in the following table 3:
TABLE 3
Example 3
The crude product of gas phase IPDI comprises n-butanol 20.05%, IPDI 38.21%, single side 31.87%, and naphthenic oil 9.87%.
The operating conditions of the lightness-removing column are controlled as follows: 11mbar at the top of the pressure tower, 24mbar at the bottom of the pressure tower, 201.5 ℃ at the bottom of the pressure tower, 26 ℃ at the top of the pressure tower and 161.2 ℃ at the lateral line; the operating conditions of the product column were: the pressure tower top is 11mbar, the tower kettle is 24mbar, the temperature of the tower kettle is 194.9 ℃, the operation temperature of the tower top is 41 ℃, and the temperature of the lateral line is 158.7 ℃.
Taking n-butanol extracted from the top of the light component removal tower, IPDI rich solution extracted from the middle side of the tower and tower kettle materials; and taking normal butanol and IPDI extracted from the top of the product tower, IPDI products extracted from the middle side of the tower and tower bottom materials. The components and contents were measured separately, and the results are shown in the following table 4:
TABLE 4
The foregoing is illustrative of the preferred embodiments of this invention, and it is to be understood that the invention is not limited to the precise form disclosed herein and that various other combinations, modifications, and environments may be resorted to, falling within the scope of the concept as disclosed herein, either as described above or as apparent to those skilled in the relevant art. And that modifications and variations may be effected by those skilled in the art without departing from the spirit and scope of the invention as defined by the appended claims.
Claims (10)
- An industrial method for purifying IPDI crude product is characterized by comprising the following steps:s1, feeding the IPDI crude product into a first rectifying tower for rectifying operation, extracting n-butyl alcohol from the tower top, extracting IPDI rich solution from the side line in the middle of the tower, and removing isophorone diamino formic acid n-butyl ester pyrolysis unit from the tower bottom material;s2, allowing the IPDI rich solution to enter a second rectifying tower for rectifying operation, extracting n-butyl alcohol and IPDI from the tower top, extracting an IPDI product from the side line in the middle of the tower, and removing materials in the tower bottom to an isophorone diamino acid n-butyl ester pyrolysis unit.
- 2. The industrial process for the purification of crude IPDI as claimed in claim 1, wherein the operating pressure of the first distillation column is 10-30mbar, the temperature of the bottom of the column is 190-210 ℃, the operating temperature of the top of the column is 20-30 ℃, and the temperature of the side line is 150-170 ℃;and/or the operating pressure of the second rectifying tower is 10-30mbar, the temperature of the tower bottom is 190-200 ℃, the operating temperature of the tower top is 30-50 ℃, and the temperature of the lateral line is 155-160 ℃.
- 3. The method of claim 1, wherein the crude IPDI product comprises n-butanol 18-30wt%, IPDI 20-45wt%, isophorone isocyanate based mono n-butyl carbamate 20-45wt%, and naphthenic oil 7-15wt%.
- 4. The industrial method for the purification of crude IPDI products according to any of claims 1 to 3, characterized in that the crude IPDI products comprise first crude products, and the preparation method of the first crude products comprises: and carrying out a first thermal decomposition reaction on isophorone diamino n-butyl formate, a solvent and a catalyst to obtain a gas phase material I, wherein the gas phase material I is the first crude product.
- 5. The industrial method for purifying crude IPDI products of claim 4, wherein the crude IPDI products further comprise a second crude product, and the preparation method of the second crude product comprises: and (3) carrying out a second thermal decomposition reaction on the tower bottom material obtained in the step (S1) and/or the step (S2) to obtain a gas-phase material III, wherein the gas-phase material III is the second crude product.
- 6. The industrial process for the purification of crude IPDI as claimed in claim 5, wherein the pressure of the first thermal decomposition reaction is controlled to-0.08 to-0.098 MPa, and the temperature is controlled to 200 to 280 ℃;and/or the pressure controlled by the second thermal decomposition reaction is-0.08 to-0.098 MPa, and the temperature is 200 to 280 ℃.
- 7. The industrial process for purifying crude IPDI according to claim 5, characterized in that the molar ratio of isophorone dicarbamic acid n-butyl ester, solvent and catalyst is: 1:0-9:0.0025-0.015.
- 8. The industrial method for purifying the crude product of IPDI according to claim 5, characterized in that the n-butyl isophorone dicarbamate is n-butyl isophorone dicarbamate product synthesized by urea method;the solvent is one of naphthenic oil, trioctyl trimellitate and trinonyl trimellitate;the catalyst is one or more of zinc picolinate, chromium picolinate, MOF-5, zinc oxide, bismuth trioxide, ionic liquid zinc, zinc chloride, zinc acetate, zinc acrylate and zinc isooctanoate.
- 9. The industrial process of purifying crude IPDI as claimed in claim 8, wherein said first thermal decomposition reaction and said second thermal decomposition reaction further yield heavy component material, and said first thermal decomposition reaction and said second thermal decomposition reaction require heavy component material removal.
- 10. Industrial process for the pyrolysis of preparing IPDI according to claim 5, characterised in that the discharged heavy component material is subjected to thermal evaporation, obtaining a gaseous product and a residue, which gaseous product, after condensation, can be used as solvent.
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